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Currently, there is a tendency to use the hardware means of information protection in extreme operating conditions, in particular, in the presence of powerful radiation. In this regard, the problem of assessing the stability of the hardware means of information protection operation is being updated, which is determined by the radiation resistance of the large digital integrated circuits (LSI) that make up them. Methods for ensuring information security in the form of static and dynamic characteristics, which are based on the use of functional-logical modeling of large digital integrated circuits (LSI) under the influence of ionizing radiation, are considered. It is shown that in some cases, information security is characterized by deterministic and non-deterministic failures when exposed to ionizing radiation. Methods for predicting the information security of LSI under the influence of ionizing radiation are proposed, which are based on models of fuzzy digital and probabilistic reliability automata. In the first case, the behavior of complex devices is determined by the specific ratio of radiation-sensitive parameters of the elements, in the second case by the statistical spread of switching moments leading to changes in the logic of the same type of sample. Moreover, the nature of their changes during irradiation depends on many factors, including the type of radiation, its intensity and spectrum, the type of criterion parameter that characterizes the radiation resistance of the LSI, and the mode of operation of the microcircuits.Conducting such a comparison is a necessary step for an adequate assessment of the radiation resistance of the LSI, which allows us to develop a procedure for analyzing the resistance of digital devices.

The methods of information security, which are based on the use of functional-logical modeling of very large digital integrated circuits (VLSI) under the influence of ionizing radiation are considered. It is shown that the multiplicity of the node and the power of the spectrum are more accurately described when using the concept of fuzzy multiplicity. Methods are proposed for predicting LSI failures when exposed to ionizing radiation, which are based on the model of fuzzy digital and probabilistic reliability automata. Moreover, the nature of their changes during irradiation depends on many factors, including the type of radiation, its intensity and range, type a criteria parameter characterizing the radiation resistance of ICs and work mode. Therefore, in different ranges of levels or intensities of the impact of the IC model can be either of fuzzy or probabilistic nature. Carrying out such a comparison is an essential step in the overall analysis of the IC radiation resistance.

The article considers digital ICs safe operation predicting methods under the influence of radiation based on fuzzy digital automaton and topological probabilistic models for assessing their performance. While ICs radiation behavior actual nature is determined by the specific ratio of the radiation-sensitive parameters of its elements and taking into account the impact of their statistical dispersion. ICs failures modeling methods under exposed to radiation, which are based on models of fuzzy digital automaton Brauer and probabilistic reliability of the machine.

We present model fits to the X-ray line spectrum of the well-known high-mass X-ray binary Cyg X-3. The primary observational data set is a spectrum taken with the Chandra X-ray Observatory High Energy Transmission Grating in 2006, though we compare it to all the other observations of this source taken so far by this instrument. We show that the density must be ≥1012 cm−3 in the region responsible for most of the emission. We discuss the influence of the dust scattering halo on the broadband spectrum, and we argue that dust scattering and extinction is not the most likely origin for the narrow feature seen near the Si K edge. We identify the features of a wind in the profiles of the strong resonance lines and show that the wind is more apparent in the lines from the lighter elements. We argue that this wind is most likely associated with the companion star. We show that the intensities of most lines can be fitted, crudely, by a single-component photoionized model. However, the iron K lines do not fit with this model. We show that the iron K line variability as a function of orbital phase is different from the lower-energy lines, which indicates that the lines arise in physically distinct regions. We discuss the interpretation of these results in the context of what is known about the system and similar systems. [ABSTRACT FROM AUTHOR]

Results of the high pressure low-temperature luminescence measurements of ZnTe:Cr2+ crystals in a diamond-anvil cell are reported. The luminescence spectra associated with the 5E- 5T2 transitions are split into three bands which exhibit quite different pressure coefficients from about 8 to 12 cm[?]1. The different values of the pressure coefficients are well explained by the Jahn-Teller effect and pressure-dependent spin-orbit interaction with second-order correction, associated with pressure-dependent admixture of the Te ligand wavefunction to the d-type wavefunction of the Cr2+ ion. [ABSTRACT FROM AUTHOR]

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated gamma-ray emission. Galactic 'microquasars', which are binary systems consisting of a neutron star or stellar-mass black hole accreting gas from a companion star, also produce relativistic jets, generally together with radio flares. Apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar, with the consequence that we are as yet unsure about the mechanism of jet energization. Here we report four gamma-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 (an exceptional X-ray binary that sporadically produces radio jets). There is a clear pattern of temporal correlations between the gamma-ray flares and transitional spectral states of the radio-frequency and X-ray emission. Particle acceleration occurred a few days before radio-jet ejections for two of the four flares, meaning that the process of jet formation implies the production of very energetic particles. In Cygnus X-3, particle energies during the flares can be thousands of times higher than during quiescent states.